U.S. patent application number 14/948636 was filed with the patent office on 2016-07-21 for solvent-free shellac coating composition.
The applicant listed for this patent is Mantrose-Haeuser Co., Inc.. Invention is credited to Katie L. Fontaine, Margaret McWeeney, Paul J. Pothier, Stephen A. Santos, Bin Zhong.
Application Number | 20160208139 14/948636 |
Document ID | / |
Family ID | 55410179 |
Filed Date | 2016-07-21 |
United States Patent
Application |
20160208139 |
Kind Code |
A1 |
Fontaine; Katie L. ; et
al. |
July 21, 2016 |
SOLVENT-FREE SHELLAC COATING COMPOSITION
Abstract
A shellac coating composition for producing a shellac coating on
a substrate comprises a fatty acid component, shellac and little or
no volatile carrier liquid. Because the fatty acid inhibits the
polymerization of the shellac when molten, the composition can be
converted into a liquid state for coating purposes by simple
heating, thereby eliminating the need for the volatile carrier
liquid.
Inventors: |
Fontaine; Katie L.;
(Rumford, RI) ; McWeeney; Margaret; (East Boston,
MA) ; Santos; Stephen A.; (Cumberland, RI) ;
Zhong; Bin; (Attleboro, MA) ; Pothier; Paul J.;
(Warwick, RI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mantrose-Haeuser Co., Inc. |
Lincoln |
RI |
US |
|
|
Family ID: |
55410179 |
Appl. No.: |
14/948636 |
Filed: |
November 23, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62103660 |
Jan 15, 2015 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A21D 15/08 20130101;
A21D 13/28 20170101; A23P 20/10 20160801; A23P 20/11 20160801; A21D
13/26 20170101; A23G 9/506 20130101; A23D 9/00 20130101; A21D 13/24
20170101; C09D 193/02 20130101 |
International
Class: |
C09D 193/02 20060101
C09D193/02; A21D 13/00 20060101 A21D013/00 |
Claims
1. A shellac coating composition for producing a coating on a
substrate, the shellac coating composition comprising a fatty acid
component and shellac, wherein the weight ratio of the fatty acid
component to the shellac is 5:95 to 95:5, and further wherein the
coating composition contains no more than 10 wt. % of a volatile
carrier liquid having an equilibrium vapor pressure at 25.degree.
C. above 0.02 atm (15.9 torr).
2. The shellac coating composition of claim 1, wherein the weight
ratio of the fatty acid component to the shellac is 5:95 to
50:50.
3. The shellac coating composition of claim 2, wherein the shellac
coating composition contains no more than 5 wt. % volatile carrier
liquid.
4. The shellac coating composition of claim 1, wherein the fatty
acid component is selected from the group consisting of a free
fatty acid, an ester of a fatty acid and a monoalcohol or dialcohol
containing 8 or less carbon atoms, a fatty acid monoglyceride, a
fatty acid digylceride, a fatty acid triglyceride, a fatty acid
phospholipid, a fatty alcohol and mixtures thereof.
5. The shellac coating composition of claim 4, wherein the fatty
acid component is selected from the group consisting of a free
fatty acid, a fatty acid monoglyceride, a fatty acid digylceride, a
fatty acid triglyceride, and mixtures thereof.
6. The shellac coating composition of claim 5, wherein the fatty
acid component is a free fatty acid.
7. The shellac coating composition of claim 6, wherein the fatty
acid component is selected from the group consisting of oleic acid,
stearic acid and palmitic acid.
8. The shellac coating composition of claim 1, wherein the shellac
coating composition is in the state of a viscous liquid or a
semi-solid paste at room temperature.
9. The shellac coating composition of claim 1, wherein the shellac
coating composition is in solid state at room temperature, and
further wherein the shellac coating composition has a softening
temperature of 40.degree. C. to 120.degree. C.
10. The shellac coating composition of claim 9, wherein the shellac
coating composition has a softening temperature of 60.degree. C. to
90.degree. C.
11. The shellac coating composition of claim 1, wherein the shellac
coating composition contains one or more additional ingredients
selected from the group consisting of a shellac plasticizer other
than a fatty acid component, a shellac polymerization retardant
other than a fatty acid component, a detackifier, a coloring agent,
a co-film former, a flavoring agent and a preservative.
12. The shellac coating composition of claim 1, wherein the shellac
coating composition is selected so that the coating produced by the
coating composition is food compatible.
13. A process for providing a shellac coating on a substrate
comprising applying to the substrate the coating composition of
claim 1.
14. The process of claim 13, wherein the weight ratio of the fatty
acid component to the shellac in the shellac coating composition is
5:95 to 50:50.
15. The process of claim 13, wherein the shellac coating
composition contains no more than 5 wt. % volatile carrier
liquid.
16. The process of claim 13, wherein the fatty acid component is
selected from the group consisting of a free fatty acid, a fatty
acid monoglyceride, a fatty acid digylceride, a fatty acid
triglyceride, and mixtures thereof.
17. The process of claim 16, wherein the fatty acid component is a
free fatty acid.
18. The process of claim 13, wherein the shellac coating
composition is in the state of a viscous liquid or a semi-solid
paste at room temperature.
19. The process of claim 13, wherein the shellac coating
composition is in solid state at room temperature, and further
wherein the shellac coating composition has a softening temperature
of 40.degree. C. to 120.degree. C.
20. The process of claim 13, wherein the shellac coating
composition is applied to the substrate by at least one of
spraying, dipping, enrobing, casting, extrusion coating, pan
coating and roller coating.
21. A coated article made by the process of claim 13.
22. The coated article of claim 21, wherein the substrate is a
bakery product.
23. The coated article of claim 22, wherein the substrate is an ice
cream cone or waffle.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to application Ser. No.
62/103,660, filed Jan. 15, 2015, the disclosure of which is
incorporated herein by reference.
BACKGROUND
[0002] Shellac has been used as a coating for a variety of
products, including food products, for many years. For example,
shellac has been used for many years as a glazing agent for
confections such as chocolate covered raisins, chocolate covered
nuts, gum balls, jelly beans, etc. In addition, shellac has also
been used for many years as a protective coating and glaze for
vitamins, tablets, various time-release preparations, and various
fruits such as apples and the like, both whole and in sections. In
addition, many patents and other publications describe using
shellac as a glazing agent for a variety of different food
products, including donuts. See, for example, the background
section of U.S. Pat. No. 6,869,628 as well as Paragraph [0006] of
U.S. 2004/0096548.
[0003] Because shellac readily polymerizes when molten, it has not
been used to coat substrates in molten form as a practical matter.
Rather, it has been necessary to dissolve or disperse the shellac
in a suitable volatile carrier liquid to produce shellac coating
compositions which are liquid enough (i.e., will flow enough) to
function as effective coating compositions.
SUMMARY OF INVENTION
[0004] In accordance with this invention, it has been found that
polymerization of shellac when molten can be inhibited by combining
it with a small but suitable amount of a fatty acid. As a result,
new shellac coating composition are provided which are solvent-free
in the sense of containing minimal and preferably no volatile
carrier liquid, it having been found that simple heating of these
compositions will make them sufficiently liquid to serve as
effective coating compositions.
[0005] Thus, this invention provides a shellac coating composition
for producing a shellac coating on a substrate, the shellac coating
composition comprising a fatty acid component and shellac, wherein
the weight ratio of the fatty acid component to the shellac is 5:95
to 95:5, and further wherein the coating composition contains no
more than 10 wt. % of a volatile carrier liquid having an
equilibrium vapor pressure at 25.degree. C. above 0.02 atm (15.9
torr).
[0006] In addition, this invention also provides a process for
providing a shellac coating on a substrate comprising applying this
coating composition to the substrate.
DETAILED DESCRIPTION
Definitions
[0007] For the purposes of this disclosure, "coating composition"
refers to a composition which can be used to form a coating on a
substrate but excludes compositions which are already in the form
of a coating on a substrate. So, for example, a coating composition
can be in the form of a coating liquid which can be poured or
sprayed onto a substrate, for example, to form a completed coating.
In addition, a coating composition can also be in the form of a
solid such as a powder, course granules, flakes or even a large
solid block, which can be melted to form such a coating liquid.
However, for the purposes of this disclosure "coating composition"
will be understood as not referring to the coating that is produced
by such a coating liquid. So, for example, a film which has been
cast upon a substrate and remains on that substrate is not a
"coating composition" in the context of this disclosure, because it
is the form of a completed coating. However, if that same film is
removed from its substrate, then it will be regarded as a "coating
composition," at least if it can be used to form a new coating such
as by melting or the like.
[0008] Also, "liquid" in reference to a coating composition means
that the coating composition has a sufficiently low viscosity so
that, after being deposited on a horizontal substrate and left
undisturbed, it will form a continuous, coherent coating on that
substrate. Also, a coating which is "continuous" in the context of
this disclosure means a coating which is not present on the
substrate in the form of discrete clumps or regions but rather is
present as an amalgamated mass. In addition, a coating which is
"coherent" in the context of this disclosure means a coating which
is free of pores and pinholes.
Shellac Resin
[0009] Shellac is a naturally occurring thermoplastic resin
obtained from secretions of the female lac bug. It exhibits a
remarkable combination of properties making it an ideal barrier
coating, these properties including low permeabilities to oxygen,
water vapor, CO2, ethylene and various odors, low lipid solubility,
excellent color and excellent clarity. Its main components are
aleuritic acid and shelloic acid.
[0010] Commercially, shellac is available in two different types,
bleached shellac and orange shellac. Moreover, both of these
shellacs are available in refined (i.e., dewaxed) as well as
unrefined (regular) versions. In addition, each of these four
different varieties of shellac are available in different physical
forms, e.g., solid flakes and aqueous and/or alcohol solutions. In
addition, some of these different varieties are also available in
different grades. For example, dewaxed orange shellac is available
in a variety of different grades ranging from yellow to red.
[0011] Shellac is obtained from seedlac, an insect secretion, by
removing debris from the seedlac and then further processing the
seedlac to obtain the desired product. As described in U.S. Pat.
No. 6,348,217, the entire disclosure of which is incorporated
herein by reference, bleached shellac is made by dissolving seedlac
in aqueous alkali and then adding a bleaching agent such as sodium
hypochlorite. The product so obtained is then precipitated and
dried to produce regular bleached shellac. Alternatively, the
dissolved bleached shellac can be refined by known techniques to
remove its wax content before precipitating and drying, thereby
producing dewaxed bleached shellac. In contrast, regular orange
shellac is made by melting seedlac, sieving out the insolubles and
then solidifying and flaking the product so obtained. Meanwhile,
dewaxed orange shellac is made by dissolving the seedlac in
alcohol, straining out the insolubles, filtering out wax particles
and passing the solution so obtained through activated carbon to
decolorize before solidifying and flaking.
[0012] These different forms of shellac have somewhat different
melting temperatures. Unfortunately, all of these forms of shellac
readily polymerize when heated above their melting temperatures.
Therefore, it is necessary when producing coating compositions from
shellac to dissolve or disperse the shellac in a volatile carrier
liquid. Examples of suitable carrier liquids that can be used for
this purpose include water, various alcohols such as methanol,
ethanol, isopropanol, etc. various ketones such as acetone, methyl
ethyl ketone, etc., various glycols such as propylene glycol, etc.,
various glycol ethers, various esters such as ethyl acetate, and so
forth. Generally speaking, these volatile carrier liquids have
equilibrium vapor pressures above 0.02 atm (15.9 torr). For
example, a typical equilibrium vapor pressure of water at
25.degree. C. is 0.03 atm (22.8 torr), of ethyl alcohol at
25.degree. C. is 0.077 atm (58.5 torr), and of 2-propanol at
25.degree. C. is 0.059 atm (44.8 torr).
[0013] In accordance with this invention, using such volatile
carrier liquids is avoided, it having been found that
polymerization of all commercial forms and grades of shellac when
heated to above their melting points can be inhibited by blending
the shellac with a fatty acid component, as further discussed
below. This is of particular importance in connection with coating
substrates which are sensitive to these volatile carrier liquids,
as contact of the substrate with these carrier liquids can be
completely avoided. Examples of such substrates include bakery
products such as biscuits, cookies, wafers, waffles and ice cream
cones, as well as various water-sensitive dry products such as
flours, grains, seeds and certain nuts.
[0014] This is also important in terms of eliminating the use of
volatile organic compounds. Ethanol and the other organic liquids
normally used to make conventional shellac coating compositions are
highly flammable as well as classified as Volatile Organic
Compounds (VOC's) under relevant federal and state statutes and
regulations. Therefore, considerable care and expense must be
undertaken when using shellac coating compositions formulated with
one or more of these VOC's as its carrier liquid. These problems
can be completely avoided by this invention, because these VOC's
are completely unnecessary.
[0015] Still another important feature of the inventive shellac
coating compositions is that the shellac coatings they produce are
highly resistant to "blushing." As well appreciated in the art,
when shellac coatings made from conventional shellac coating
compositions are exposed to water, they often develop a significant
whitish haze, which is known in the art as "blushing." This problem
is essentially avoided in accordance with this invention, as the
shellac coatings produced by the inventive shellac coating
compositions are largely resistance to this blushing
phenomenon.
Fatty Acid Component
[0016] Fatty acids are aliphatic carboxylic acids whose carbon
chains contain 4 to 28 carbon atoms. Fatty acids can be saturated
as well as unsaturated with one, two, three, four or more ethylenic
unsaturation groups. Fatty acids whose aliphatic tails contain
fewer than six carbon atoms are generally regarded as short chain
fatty acids (SCFA). Fatty acids whose aliphatic tails contain 6-12
carbon atoms are generally regarded as medium chain fatty acids
(MCFA). Fatty acids whose aliphatic tails contain 13-21 carbon
atoms are generally regarded as long chain fatty acids (LCFA).
Fatty acids whose aliphatic tails contain 22 or more carbon atoms
are generally regarded as very long chain fatty acids (VLCFA). Most
naturally occurring fatty acids have an even number of carbon
atoms. All such fatty acids can be used as the fatty acid component
of the inventive shellac coating compositions.
[0017] In addition to the above "free" fatty acids, numerous fatty
acid derivatives can also be used for this purpose. Examples
include esters of such free fatty acids with monoalcohols or
dialcohols containing 8 or less carbon atoms, fatty acid
monoglycerides, fatty acid digylcerides, fatty acid triglycerides,
fatty acid phospholipids, fatty alcohols and mixtures thereof.
Esters of free fatty acids with monoalcohols or dialcohols as well
fatty acid monoglycerides, digylcerides and triglycerides are
interesting, while free fatty acids and especially oleic acid,
stearic acid and palmitic acid are especially interesting.
[0018] As well understood in industry, these free fatty acids and
analogues are available in a number of different grades, e.g., food
grade, industrial grade, etc. All of these different grades can be
used in this invention, it being desirable of course that the
particular grade selected for a particular application comply with
the legal regulations applicable to that application.
Additional Ingredients
[0019] In addition to shellac and fatty acid component, the
inventive shellac coating compositions can also contain additional
ingredients to improve the properties of these coating compositions
as well as the coatings they produce.
[0020] For example, the inventive shellac coating compositions can
contain a polymerization retardant to help slow the polymerization
of the shellac, examples of which include sodium hydroxide,
potassium hydroxide and potassium acetate.
[0021] In addition, the inventive shellac coating compositions can
contain an organic origin (i.e., plant or animal origin) co-film
former. Examples include certain microcrystalline cellulose; waxes
such as paraffin wax, carnauba wax, beeswax, candelila wax and
polyethylene wax; various naturally-occurring resins such as wood
resin; and coumarone-indene; and various proteins including corn
zein (a-zein, b-zein and/or v-zein), wheat gluten, soy protein,
peanut protein, keratin, collagen, gelatin, milk protein (casein)
and whey protein.
[0022] The inventive shellac coating compositions can also contain
other types of film formers including organic-origin film forming
materials not exhibiting the above water vapor resistance
properties. Examples include microcrystalline cellulose; starches
and derivatives such as raw starch, modified starch, pregelatinized
starch, dextrin, maltodextrin corn syrup sucrose, dextrose/fructose
and sugar polyols; extrudate gums such as gum arabic, gum ghatti,
gum karaya and gum tragacanth; seed gums such as guar gum and
locust bean gum; microbial fermentation gums such as xanthan,
gallan gum and chitosan; seaweed extracts such as agar, alginates,
carageenans and furcellaran; and pectins.
[0023] The inventive shellac coating compositions can also contain
plasticizers other than lipids such as polyethylene glycol (PEG),
polypropylene glycol (PPG), and the like; coloring agents such as
organic pigments and inorganic pigments, dyes and other naturally
occurring colorants; flavorants and preservatives.
[0024] To aid in their application to substrates when in powder
form, the inventive shellac coating compositions can also contain
conventional flow control agents such as silicates, stearates, and
the like.
[0025] Mixtures of these different additional ingredients, of
course, can be used.
Method of Manufacture
[0026] The inventive shellac coating composition can be easily made
by heating the fatty acid component to above the melting
temperature of the shellac and then adding the shellac, preferably
in the form of a comminuted solid, and preferably in increments, to
the fatty acid component with continued heating and mixing until a
homogeneous blend is obtained. Any additional ingredients are
preferably added at this time, although they can be added earlier
if desired.
[0027] When the inventive shellac coating composition is intended
to be applied to a substrate by extrusion coating, another way it
can be made is by combining its ingredients together in a common
feed hopper used for feeding the extruder or, alternatively, by
feeding these ingredients to the extruder by means of separate feed
hoppers with these ingredients being blended together inside the
extruder as it melts and deposits these materials on the substrate
being coated.
Proportions of Ingredients and Properties
[0028] The relative amounts of shellac and fatty acid component in
the inventive shellac coating compositions can vary widely, and
essentially any amount can be used. Normally, the weight ratio of
fatty acid component to shellac is between 5:95 and 95:5. Within
these broad limits, shellac coating compositions containing no more
than 80 wt. % fatty acid component, based on the combined weights
of the fatty acid component and shellac are interesting, with those
containing no more than 65 wt. % fatty acid component, no more than
50 wt. % fatty acid component, no more than 45 wt. % fatty acid
component, no more than 40 wt. % fatty acid component, no more than
35 wt. % fatty acid component and even no more than 30 wt. % fatty
acid component, on the same basis, being more interesting.
Normally, the weight ratio of fatty acid component to shellac is
between 10:90 and 50:50.
[0029] If additional ingredients are included in the inventive
shellac coating compositions, the total amount (concentration) of
these additional ingredients in the inventive shellac coating
compositions is desirably no more than 25 wt. %, based on the
weight of the entire coating composition. More desirably, the total
amount (concentration) of these additional ingredients in the
inventive shellac coating compositions is no more than 15 wt. %, no
more than 10 wt. %, no more than 5 wt. %, no more than 2 wt. %, no
more than 1 wt. %. or even no more than 0.5 wt. %.
[0030] As indicated above, the inventive shellac coating
compositions are either free or essentially free of a volatile
carrier liquid having an equilibrium vapor pressure at 25.degree.
C. above 0.02 atm (15.9 torr). Thus, the inventive shellac coating
compositions are either free or essentially free of water (vapor
pressure at 25.degree. C. of 0.03 atm /23.8 torr) of ethyl alcohol
(vapor pressure at 25.degree. C. of 0.077 atm/59 torr) and of
2-propanol (vapor pressure at 25.degree. C. of 0.059 atm/45 torr).
"Essentially free" in this context means that the inventive shellac
coating compositions contain no more than 10 wt. % of the volatile
carrier liquid. More commonly, however, the inventive shellac
coating compositions contain no more than 5 wt. %., no more than 2
wt. %, no more than 1 wt. %, no more than 0.5 wt. %, or even no
more than 0.1 wt. % of such a volatile carrier liquid. Nonetheless,
they can easily be converted to a liquid state for coating purposes
by heating them to above the melting temperature of the shellac
ingredient they contain.
[0031] As previously indicated, it has been found in accordance
with this invention that the fatty acid component of the inventive
shellac coating compositions acts as a polymerization inhibitor,
thereby inhibiting polymerization of the shellac ingredient of
these compositions when heated to elevated temperatures. As a
result, new shellac coating composition are provided which are
essentially free of volatile carrier liquids yet can be made
sufficiently liquid to serve as effective coating compositions by
simple heating.
[0032] The physical form of the inventive shellac coating
compositions can vary widely. Depending on the relative amounts of
shellac and fatty acid component, the type of fatty acid component
and the type of optional additional additive, if any, the inventive
shellac coating compositions may take the form of a viscous liquid,
a paste-like semi-solid state (i.e., too viscous to flow by gravity
yet not a hard solid either) such as butter or bees wax or a solid
rigid mass at room temperature. Moreover, if in a solid state they
can assume any structure ranging from a large solid block, chunks,
granular solids, fine powders, and even thin films produced by
removing a cast film from a substrate. In addition, if in a solid
state at room temperature, they can assume a wide range of melting
or softening points, typically ranging from 10.degree. C. to
90.degree. C. Within this broad range, those exhibiting melting or
softening points of at least 20.degree. C., at least 30.degree. C.,
at least 40.degree. C., and at least 50.degree. C., are more
interesting.
[0033] The physical and chemical properties of the shellac coatings
produced by the inventive shellac coating compositions can also
vary widely, depending on the relative amounts of shellac and fatty
acid component, the type of fatty acid component and the type of
optional additional additive, if any, included in these coating
compositions. By suitable selection of these variables, skilled
shellac chemists should have no difficultly in producing shellac
coating compositions having the same or essentially the same
hardness, flexibility, barrier properties and other properties as
shellac coatings made by conventional techniques.
Substrate
[0034] The inventive shellac coating compositions can be used to
provide shellac coatings on any and all types of substrates
previously provided with shellac coatings. For example, the
inventive shellac coating compositions can be used to provide
shellac coatings on industrial substrates such as wood, metals,
plastics, etc. In addition, edible substrates including fruits such
as apples, pears, etc.; vegetables: bakery products such as
biscuits, cookies, wafers, waffles, ice cream cones, and other
dough based products; candy such as solid chocolate bars, pastilles
etc. as well as chocolate coated or embed products chocolate coated
biscuits and cookies; pharmaceuticals such as pills, lozenges, etc.
can also be coated with the inventive shellac coating compositions,
it being desirable of course to use food grade ingredients and
processing equipment for this purpose. Products intended to come
into contact with food and/or pharmaceuticals such as fiber box
board, food service trays, utensils, etc., can also be coated with
the inventive shellac coating compositions, again it being
desirable to use food-contact approved grade ingredients and
processing equipment for this purpose.
[0035] In one embodiment of this invention, the inventive shellac
coating compositions can be used to form cast, free-standing films.
In this embodiment, conventional substrates used for producing
cast, free-standing films from other similar materials can be used
for this purpose.
Method of Application
[0036] The inventive shellac coating compositions can be applied to
substrates by any appropriate coating technique, examples of which
include spraying (both traditional and electrostatic spray
techniques), dipping, enrobing, casting, extrusion coating, pan
coating and roller coating. Normally, this means that the inventive
coating composition, if in a solid state at room temperature, will
need to be heated until the composition assumes a liquid state
prior to the application of the coating composition to its
substrate. So, for example, if the inventive coating composition is
applied by dipping, enrobing, casting, hot melt spraying, roller
coating, or some types of pan coating techniques, the coating
composition will normally be heated to a liquid state before it is
applied. Since the fatty acid component of the inventive shellac
coating compositions inhibits polymerization of the shellac
ingredient in these compositions, this is of little or no
concern.
[0037] In certain applications, the inventive shellac coating
compositions can be heated to a liquid state as part of the coating
process. This can occur, for example, if the inventive shellac
coating composition is applied by extrusion coating techniques. In
addition, this can also occur if the inventive shellac coating
composition is applied by certain types of spray coating
techniques, for example, via melt spraying or by electrostatic
spraying of the composition in the form of a dry powder. This can
also occur if the inventive shellac coating composition, in the
foam of a particulate, is applied to a substrate which has been
previously heated enough so that the latent heat in the substrate
melts the particulate, thereby forming a coating. In some
situations, an additional heating step may be used to subject the
substrate to heating after the powder is applied if necessary.
Heating may occur both before and after application as
necessary.
[0038] A particular advantage of the inventive coating composition
when directly applied to bakery product substrates such as
biscuits, cookies, wafers, cones, and other dough based products is
that the crispness of the underlying substrate is preserved. This
is difficult or impossible to do when conventional shellac coating
compositions are used in this way, because the carrier liquid in
the coating composition is normally absorbed by the bakery product
substrate. This problem is eliminated when the inventive shellac
coating composition is used, because it contains no carrier
liquid.
[0039] In another application, the inventive coating composition is
used as an adhesive, or carrier, for components to be added to a
substrate's surface. For example, various food adjuvants such as
drugs, medications, vaccines, food supplements, etc., can be added
to many different types of food substrates such as whole grains,
breads, flours, and other food items by coating them with the
inventive coating composition which has been fortified with the
food adjuvant.
[0040] Finally, the inventive coating composition, when in the form
of a fine powder, can also be used as a polishing agent by
combining it with a batch of the substrate to be treated, e.g.,
tablets, confections, or the like, in a suitable mixing device such
as panning equipment or a tumbling apparatus which generates enough
friction between these materials so that a polished surface on the
substrate is produced. This buffing process can enhance surface
characteristics of the substrate, adding a polished effect, as well
as producing a coating which provides slip characteristics, barrier
to moisture, etc.
WORKING EXAMPLES
Example 1
[0041] The following hot melt blends were prepared:
TABLE-US-00001 TABLE 1 Shellac Fatty Acid Blend Ratio (Fatty
Acid:Shellac) Refined Orange Oleic Acid 18:82 Stearic Acid 18:82
Palmitic Acid 50:50
[0042] To prepare the blends listed in Table 1 above, the fatty
acid of each composition was heated to above the melting point of
the refined (dewaxed) orange shellac in a suitable container
(aluminum pan or glass beaker of appropriate size). With slow
mixing, the dewaxed orange shellac was melted and blended into the
molten fatty acid in a stepwise fashion. From this point forward,
the molten blend was allowed to cool to form the inventive hot melt
blend in its solid phase.
[0043] Each blend produced an opaque semi-malleable solid, able to
be returned to a molten state upon reheating to above its melting
point. The softening points of the above hot melt blends ranged
from about 60.degree. C. to 85.degree. C.
Example 2
[0044] The following hot melt blends were prepared:
TABLE-US-00002 TABLE 2 Fatty Acid Shellac Blend Ratio (Fatty
Acid:Shellac) Oleic Acid Refined Orange 33:67 Orange Flaked 33:67
Refined Bleached 33:67 Regular Bleached 33:67
[0045] To prepare the blends listed in Table 2 above, the selected
fatty acid was heated to above the melting point of the shellac
type used in each example in a suitable container (aluminum pan or
glass beaker of appropriate size). With slow mixing, the
appropriate amount of shellac was melted and blended into the
molten fatty acid in a stepwise fashion. From this point forward,
the molten blend was allowed to cool to form each inventive hot
melt blend in its solid phase. Each blend produces an opaque,
semi-malleable solid for further use.
Example 3
[0046] A hot melt blend comprising: 43 parts by weight dewaxed
orange shellac and 57 parts by weight of a mixture of oleic acid
and stearic acid was prepared by the same procedure described above
in connection with Examples 1 and 2. This molten product was
applied to a coated sheet of cardstock suitable for the release of
the finished product, after which the product was allowed to cool
to a solid state. The solid product so formed was then removed from
the substrate and ground into large flakes approximately 1 in.sup.2
(.about.645 mm.sup.2) in size.
Example 4
[0047] A portion of the flakes produced in the above Example 3 was
placed into the feed chamber of a hot melt spray gun designed for
spray application of waxes (supplied by Glue Machinery Corporation)
and allowed to melt at a set temperature for a period of 10
minutes.
[0048] After melting, the composition was sprayed onto an edible
waffle cone substrate at an application rate of about 18% of the
total dry weight of the coated edible substrate. The applied
composition was then allowed to cool to room temperature, thereby
forming a solid shellac coating providing the substrate with extra
or enhanced properties ranging from enhanced physical appearance,
enhanced strengthening and enhanced barrier properties such as an
enhanced resistance to the transmission of liquids such as water,
milk and melted ice cream as well as vapors emanating from such
liquids.
[0049] Although only a few embodiments have been described above,
it should be appreciated that many modifications can be made
without departing from the spirit and scope of the invention. All
such modifications are intended to be included within the scope of
this invention, which is to be limited only by the following
claims:
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